#include<stdio.h>
int x,v,minite,hour,t_hour;
int main(void)
{
    scanf("%d %d",&x,&v);
    minite=x/v+10;
    hour=minite/60;
    for(t_hour=31-hour;t_hour>24;t_hour-=24)
    {;}
    minite%=60;
    if (x%v!=0)
        minite++;
    minite=60-minite;
    printf("%02d:%02d",t_hour,minite);
    return 0;
}